Polyphonic Synthesizer:

Modal 002
Modal 008 (for sale)
Moog One 16
Nonlinear Labs C15
Waldorf Quantum
Waldorf XTk30
Wersi Stage Performer

Monophonic Synthesizer:

Casio VL-1 Tone
Dübreq Stylophone
Korg M500 MicroPreset (for sale)
MeeBlip (for sale)
Modal 001 (for sale)
Modal Craft Synth
Modal Skulpt
Modulus monoWave
Moog miniMoog (1979 & 2017)
Moog Minitaur
Moog Prodigy
Moog Sub Phatty
Moog Taurus III
Moog Voyager
Sequential Circuits Pro-One
VacoLoco Zira
Waldorf Pulse (for sale)
Waldorf Pulse 2


Synth-Werk Modular
Synthesizers.com Modular


Korg MS-20 mini (for sale)
TTSH (ARP 2600 clone)

String Machines:

ELKA Rhapsody 610
Eminent 310 theatre (for free!)
Hohner String Vox
Logan String Melody
Waldorf Streichfett

Other Keyboards:

Manikin Memotron
Mellotron Micro


ARP Sequencer (clone)
Behringer Mixer MX2642A
Behringer Mixer MX8000
Behringer Rack Mixer RX1602
Boss DR-220E
Digital Raagini
EEH DS 500
Electro-Harmonix Small Stone
Georg Mahr Midi-Ratsche
Ibanez Digital Delay DM1000
IBK 10 Control
Kurzweil XM-1 Expression-Mate
Lexicon Model 200 reverb
Modal Craft Rhythm
Mode Machines Krautrock Phaser
Moogerfooger Ring Modulator 102
Moogerfooger 12-Stage Phaser 103
Moogerfooger Analog Delay 104Z
Moogerfooger Murf 105
Moog MP201
OTO Machines BAM
Roland TR-08
Schrittmacher's Inside
Schulte Compact Phaser (19")
Simmons SDS-V
Strymon Timeline
Synthoma Élkorus
VacoLoco Tron
Waldorf 4Pole
Waldorf EQ27
Wersi Voice (BBD FX)
Waldorf midiBay
Waldorf Becher/Mugs


Access MicroWave controller
Alesis Andromeda A6
ARP (Korg mini) Odyssey
ARP Quartet
Crumar Multiman S
Crumar Performer
EES Midi CV7
ELKA Solist 505
ELKA x705
Emu Emax II
Farfisa Soundmaker
Farfisa Syntorchestra
Grp A4
Hohner ADAM
Hohner String Performer
Jen SX1000
Kawai SX-210
Keio Mini Pops 3
Korg PE1000 (Poly Ensemble)
Korg PE2000 (Poly Ensemble S)
Moog Satellite
Oberheim Matrix 6
PPG waves
PPG wave 2.3 (V8.3)
Rhythm Ace 2l
Roland TR 606
Roland M-VS1
SCI model 700
Seiko DS 202+310
Sound-Art Chameleon
Technosaurus Cyclodon
Vermona Piano-Strings
Waldorf Blofeld
Waldorf microQ keyboard
Waldorf Q
Waldorf XT30
Waldorf Gekko Chords
Waldorf Gekko Arp
Waldorf microWave
Waldorf rackAttack
Waldorf Wave
Waldorf waveSlave
Wersi Baß Synth
Wersi String Orchestra


K. Schulze's "Sense"

Helper Apps:

Hz-2-cent Calculator

M@ail & Impressum

© Till Kopper
Electronic Engineering Hoffman DS 500 Sequencer

EEH DS500 frontplate

EEH baute den Banana Synthy und einige Sonderanfertigungen von Sequenzern für Tangerine Dream und Klaus Schulze.
Wuppertal, Deutschland, etwa 1982 (?), Auflage unbekannt. Benutzt von Klaus Schulze (es gibt ein Foto von KS mit EEG DS500), Till Kopper, Frank Klare und ?
Digitaler 500 Schritte monophoner Sequenzer mit Spannungsausgängen.
Schwarzes Metalgehäuse mit etwa 20/15/6 cm (Breite, Tiefe, Höhe)

EEH built the Banana Synth and some custom sequencers for Tangerine Dream and Klaus Schulze
Wuppertal, Germany, about 1982 (?), # built ? Used by Klaus Schulze (there is one photo of KS with an EEH DS500), Till Kopper, Frank Klare and ?
Digital 500 Steps Sequencer monophonic with Voltage/Gate Interface
Black metal box about 8/6/2.5 inches (width/deep/high).

Vorne / Frontpanel

3 digit 8-segment LED display
speed knob
bypass switch
matrix of 4 rows and 5 colums of buttons:

left colum:
C (= Control Voltage = used as pitch most times) with yellow LED
T (= Time = note value) with yellow LED
D (= Duration = gate time) with yellow LED
L (= loop) with yellow LED

second colum:

third colum:
Start/Stop button with red LED

fourth colum:
+ (next step) with red LED

fifth colum:
M (= mode selector/ pushed twice= step recording) with green LED
I (= load extern= "realtime" recording) with green LED
G (= goto/ tape in) with green LED
- (= goto last step/ tape out) with green LED

Hinten / Backpanel

on/off switch
power in (9-15 Volts) 3,5 mm jack
tape in/out as one (1!) RCA socket
(you have to swap jacks to send or receive from tape)
clock out (Voltage trigger)
clock in (dito)
gate out (to be switched from S to V-trigger with mini switches inside the box)
gate in (dito)
CV out (1 Volt/octave / to be finetuned inside the box)
CV in (1 Volt/octave / to be finetuned inside the box)

Innenleben / Inside

EEH DS500 inside detail chips

Durch das Umschalten des Dip-Schalters Nr. 3 auf AUS gibt es am Gate-Ausgang einen V-Gate. Hier steht er auf AN und somit auf Switch-Gate
By setting the dip-switch #3 to OFF, you get a voltage gate out. Here it is set to ON and there for you get S-gate

  • based on NEC D780C Z80 CPU
  • 500 steps availible
  • 5 octaves span (= 60 notes = slightly less then 2^6 = 6 bit covers it all)
  • 8 bit DAC using 6 bit only
  • max note lengh 32 clock tickings
  • max note duration 31 clock tickings (0= pause)
  • Schleifenzähler, deshalb kann man Schleifen innerhalb von Schleifen erstellen.
    loops with counter, therefore you can built loops inside loops!
  • 2 accumulators each 1.2 Volts for memory buffering

Und wie zu meistern / How to master

Um eine Schleife eines C-Dur Arpeggio in der zweiten Oktave ab dem Schritt 250 zu programmieren muß man "nur" eintippen:
To program a loop of a C maj arpeggio in the second octave starting at memory location 250 you have "only" to type:

250 G go to step 250
M (2x)enable program mode and selecting step recording (LED of the M-button = on, other green LEDs = off)
200 C 2nd octave no halfstep = C
 unit jumps to the next step after every use of the C, T, D or L command
204 C 2nd octave and 4 halftones above the C = E
207 C 2nd octave and 7 halftones above the C = G
250 L jump to step 250
001 T looping endless, a different value x would loop x times and would go after that to step selected above
250 G goto step 250
004 T note lenght = 4 ticks of the clock
004 T you could also just type T when the value stays the same as before
004 T you could also just type T when the value stays the same as before
250 G go to step 250
003 D note duration = 3 ticks of the clock
003 D you could also just type T when the value stays the same as before
003 D you could also just type T when the value stays the same as before
M (4x)exit program mode (all 4 green LEDs = off)

Wie man sieht war das ganz musikalisch zu programmieren ;-)
As you can see it was really musical to program ;-)

Um die Sequenz abzuspielen muss man:
To play this sequence you have to:
250 G go to step 250
S-button = start/stop

Extras /special

Mein am 24.4.87 gebraucht gekauftes Exemplar hat paar Modifikationen vorne am Gehäuse
On my unit (bought used 24th April 1987) are some special outputs in front of the box

Diese Modifikationen wurden von EEH ausgeführt:
These modifications were made by EEH:
  • MIDI Ausgang (nur Kanal 1) mit MIDI Clock Ausgabe
    Midi out (chanel 1 only) with MIDI clock output
  • Clock Ausgang mit Viertel-Teilung der Master Clock (= blinkendes LED der +Taste / NICHT GEPUFFERT !)
    Clock out at quarter speed of the master clock (= blinking LED of the + button / NOT BUFFERT !)
Bitte kontaktieren, wenn Sie Interesse an der MIDI Modifikation haben sollten (MIDI-Buchse, 3 Kabel, 2 Widerstände, neuer EPROM).
Please contact, if you are interested in the MIDI modification (MIDI socket, 3 wires, 2 resistors, new EPROM).

Diese Modifikation wurde kürzlich ausgeführt:
This modification was made recently:
  • Auslaufende Puffer-Akkus gegen neue in Halterungen ausgetauscht
    Leaking accus exchanged for new ones in holders

EEH DS500 inside

Quellen /Resources

Copyright: Thomas Hopf (www.elink.de)